Joining System and Use of this System

ABSTRACT

The present invention relates to a joining system for joining two elements ( 1, 2 ), for example a pillar and a beam in a building construction, where a first part ( 3 ) of the joining system comprises an outer box element ( 10 ) and at least one internal box element ( 20 ) for insertion in the outer box element ( 10 ) comprising a locking device for locking the internal box element ( 20 ) to the outer box element ( 10 ) and a joining element ( 22 ) for cooperation with a second part ( 4 ) of the joining system and where the second part ( 4 ) of the joining system can be attached in the second ( 2, 1 ) of the two elements that have to be joined, where the locking device comprises a snap-in device that works in conjunction with cut-outs ( 12 ) provided in the outer box element ( 10 ).

The present invention relates to a joining system for joining two elements, for example a pillar and a beam in a building construction.

During the erection of building structures there is a need to find a simple way of joining building elements that are manufactured at another location, for example pillars and beams, in order to form a framework for the building, or alternatively to join step elements in a staircase or the like. Another issue is that it should be possible to join these elements in a simple manner, involving as little dangerous work as possible for the personnel who have to join the elements. Another point is that the joining operation should not be time-consuming and that the actual elements that are to be joined should be easy to manufacture and transport to the building site. A building component is easy to transport and occupies least space during transport if it has as few projecting parts as possible.

Several alternative solutions exist today for joining elements. One example is described in the patent publications GB 1 400 595, describing a system where a box element which is open at one side is cast into a concrete pillar and a corresponding box is cast into an end edge of a beam. In the box in the beam, an interior loose element is provided which, when pillar and beam are joined, is moved by means of a fluid, partly out of the beam box into the box in the pillar, thus forming a bridge element between the parts. In this position the bridge element is locked by a rod that is inserted into a through-going hole in the pillar, which hole also passes through the box element in the pillar and the part of the bridge element located in the pillar. In a similar manner a rod is inserted in a hole passing transversely through the beam and thereby also the box element in the beam and the part of the bridge element located there. This solution has several disadvantages; firstly the interior bridge element has to be inserted in one of the boxes before the elements are lifted so that the openings on the boxes are aligned with each other, whereupon the element has to be moved so that it is disposed in both boxes. A further drawback is connected with the accurate adjustment that is necessary in order for the boxes to be aligned with each other followed by the necessity of moving the bridge element in some way or other. Moreover, several locking rods have to be inserted manually in holes in the pillar and beam and the bridge element which thereby also has to be correctly located relative to the box elements in order for it to work. This solution is time-consuming, requires a great deal of manual work at the joining location and is therefore also a relatively dangerous solution for the personnel who have to carry out the work. The solution also requires all the elements to be correctly positioned in order to lock the system without any self-adjustment.

The contractor Peikko® has a solution, a so-called PC console, in its systems where a fastening element is cast into a pillar so that it is in alignment with the pillar's outer surface. To this fastening element which is cast into the pillar, an intermediate piece and a foot part are secured by screw connections. These parts are secured to the fastening part by screw connections and this is done at the work site. The beams in this system have a shoe part mounted on their end surfaces which works in conjunction with the foot part secured to the pillar. With this solution, however, it is relatively time-consuming to secure the intermediate piece and the foot part to the fastening element with screw connections and there are a relatively large number of parts that have to be secured to one another at the installation site.

The object of the present invention is to provide a solution which offers the same advantages as previously known solutions, but in which in addition the joining process is easier and less time-consuming and where there are fewer parts in the system.

The above-mentioned objects are achieved with a joining system with the individual parts as indicated in the attached claims and as described below.

According to the invention a joining system for joining two elements, building elements, comprises two parts; a first part which is mounted in one element and a second part which is mounted in the second element. These parts work in conjunction in such a manner that they interlock the elements in a simple fashion. The elements that have to be joined may, for example, be a pillar and a beam in a building construction. The elements may also be other elements such as step elements and staircases. The elements may be steel parts where the parts of the joining system are welded or affixed in another way to the elements, but at least one of the elements is preferably a cast element, for example of concrete, but a composite or plastic element or another material that has to be cast may also be envisaged.

A first part of the joining system for attaching to one of the two elements comprises an outer box element comprising attachment devices for attaching reinforcing elements, or alternatively it is conceivable that these attachment devices are devices for welding the box element to a metal part, or devices for welding reinforcing elements. The box element may also have different types of attachment devices for attaching different types of reinforcement. The first part further comprises at least one internal box element for insertion in the outer box element. The internal box element comprises a locking device for locking the internal box element relative to the outer box element and a joining element for cooperation with a second part of the joining system. The locking device preferably comprises a snap-in device, cooperating with cut-outs provided in the outer box element, with the result that the boxes are locked together in a very simple manner, without, for example, the use of tools at the installation site. In this way the internal box element is locked directly to the external element by insertion in the external element, so that it is in the correct position. A locking operation of this kind is thereby achieved quickly with the minimum of manual work.

The outer box element is mounted in the first element, for example by casting thereof, in such a manner that an open side of the outer box element is aligned with the surface of the first element. In this way the first element can be transported to the building site without projecting parts. The internal box element can also be inserted in the outer box element before the first element is handled, lifted or raised at the building site in order to form a part of the building construction, thereby also reducing the risk to the personnel involved in the work.

The second part of the joining system comprises a plate element mounted on the part of the second element facing the first element, where the plate element comprises a cut-out complementary to the joining element of the internal box element of the first part of the joining system. In this way the second element may, for example, be hoisted up and lowered over the joining element mounted on the first element, and by means of this movement centred and secured relative to the other element and thereby locked against movement in a substantially horizontal plane.

In an embodiment the snap-in device mounted on the internal box element comprises two through-going holes arranged in two oppositely directed lateral surfaces and a tubular piece provided in the two through-going holes, wherein there are provided in the tubular piece two locking pieces with an intermediate spring element, where the locking pieces work in conjunction with cut-outs in the outer box element. Several variants of such a snap-in device may be envisaged here, but what is important is that there are elements in the internal box element that are pretensioned in order to work in conjunction with cut-outs in the outer box element, or alternatively the reverse case where locking elements prestressed in the outer box element work in conjunction with cut-outs in the internal box element. The case may also be envisaged where the snap-in device has a one-sided snap-in device, with only one element that works in conjunction with a cut-out in the outer box element, or alternatively a four-sided snap-in device.

The cut-outs in the outer box element are preferably in the form of two through-going holes in the box in two oppositely directed sides of the outer box element with externally located caps. These holes may be of any shape; round, oval, triangular, etc. Alternatively, the cut-outs in the outer box element do not need to be through-going, but only internal grooves. The function of the caps is to prevent casting material in a casting process of one element from infiltrating the outer box element located in the casting mould for the one element before it is cast.

The cut-outs in the outer box element preferably have a cross sectional shape corresponding to the locking pieces in the snap-in device, but it is also conceivable for them to have a different shape to make it easier to insert the internal box element in the outer box element and lock them together.

In an embodiment the outer box element comprises four surrounding sides, for example a piece of a box beam and a rear side, for example a plate welded on to the piece of the box beam, thus forming a partly closed box with one open side. When arranged in an element, the open side of the outer box element is facing out of the element, and the internal box element will be inserted into this open side of the external element, and where the end edge of the box element facing away from the rear plate is aligned with an external surface of the element in which it is to be mounted.

The internal box element may also be composed of a box element with four surrounding sides, for example a box beam with a slightly smaller cross section than the outer box element. The internal box element also has a length which is such that when it is inserted in the outer box element it has a portion which projects a length from the outer box element. The internal box element also has a joining element in the form of a plate element mounted on the projecting portion of the internal box element.

Other cross sectional shapes than square-shaped may of course also be envisaged for the box beams and the invention is not limited to a square shape. Several box elements may be arranged inside one another, or alternatively two internal box elements beside each other internally in an outer box element. In an embodiment with a two-sided snap-in device, the outer box element may comprise additional grooves that work in conjunction with grooves on the internal box element in order to ensure that the internal element is correctly inserted in the outer box element, if it is essential for it to be inserted in a particular direction. If the orientation of the internal box element is of no importance, for example whether the locking device has locking elements on one or two sides while the outer box element has cut-outs in all four sides, the internal box element may be inserted with an arbitrary orientation. Alternatively, the locking devices may have locking elements on all four sides that work in conjunction with cut-outs in all four surfaces of the outer box element.

The first part of the joining device may also comprise devices which indicate whether the internal box element is locked to the outer box element. These may be visual or sensory devices, for example in the embodiment indicated, in a cut-out in a tubular piece extending through the internal box element, thus permitting a visual check whether the locking pieces have moved out into the cut-outs in the outer box element.

It is also conceivable for the internal box element to comprise devices that permit the internal and the outer box elements to be released from each other again after locking, such as for example in the embodiment indicated where there is a withdrawal device located inside the internal box element, thus enabling the locking pieces to be pulled into the internal box element against the spring and out of engagement with the outer box element. This may also be a device that can be used to facilitate the insertion of the internal box element in the outer box element, by enabling the locking pieces of the snap-in device to be retracted so that they do not project outside the internal box element when it has to be inserted in the outer box element. A movable and/or removable external sleeve, for example, may also be provided round the internal box element that holds the locking elements in a retracted position until the locking pieces are located at least partly inside the outer box element. This external sleeve may be moved by the edge of the outer box element on insertion of the internal box element into the outer box element or it may be removed in a more manual fashion.

The joining system may be employed for joining two elements or for joining several elements to one element, for example for joining two or more beams to a pillar round the same point on the pillar. In this case a first part of a joining system is provided, for example an outer box element, at least two sides of the pillar. In the preferred embodiment at least some of the reinforcing elements in the cast part for these two outer box elements are provided with attachment devices, for example a threaded portion, at both ends and arranged in such a manner that the reinforcing element is secured in attachment devices in the two box elements so that these two box elements are secured to each other. The two outer box elements are preferably arranged at two oppositely directed sides of the pillar, but reinforcing elements may also be envisaged that are bent at ninety degrees, and there may also be three or four or more outer box elements secured to one another. The reinforcing elements are preferably straight reinforcing rods with threaded portions at both ends, so that it is easy to attach the two outer box elements and obtain the correct distance between them, with the result that they are in alignment with the external surface of the element wherein they are to be cast. An alternative scenario is that they are threaded at one end and comprise an upset, a stop device or the like at the other end of the reinforcing element or they may only be welded at the other end.

The joining system is preferably employed in such a manner that the first part of the joining system, with internal and outer box elements, is cast into a pillar. The second part may be cast into a beam or secured to a non-cast beam. An alternative application is where both parts of the joining system are arranged in cast elements. Cast elements here should be understood to mean all types of cast elements, concrete, plastic, composite, etc. The joining system may also be envisaged attached to other types of elements than cast elements, for example welded to steel structures.

The invention will now be explained by a non-limiting explanatory embodiment, with reference to the attached drawings, in which;

FIG. 1 illustrates a joining system according to the invention employed for joining a pillar and a beam, viewed from the side,

FIGS. 2A-C illustrate a first part of the joining system in FIG. 1, where FIG. 2A is a perspective view, FIG. 2B a view from the side and FIG. 2C a partial sectional view along line A-A in FIG. 2B,

FIGS. 3A-B illustrate an outer box element as illustrated in FIG. 2, where FIG. 3A is a perspective view and FIG. 3B is a view from in front into the box element,

FIGS. 4A-B illustrate an internal box element as illustrated in FIG. 2, where FIG. 4B is a perspective view and FIG. 4A is a rear view into the box element,

FIGS. 5A-B illustrate the second part of the joining system in FIG. 1, where FIG. 5A is a view from the underside of the beam and FIG. 5B is a view towards an end of the beam, and

FIG. 6 illustrates two alternative methods of attaching a first part of the joining system to a beam.

In the following explanation, reference is made to all the figures, but where special figures are involved, this is indicated.

FIG. 1 illustrates a joining system according to the invention for joining a beam 2 to a pillar 1, where the joining system comprises a first part 3 mounted in the pillar 1 and a second part 4 mounted in the beam 2. The individual elements will be explained in more detail with reference to the other drawings. The first part of the joining system is shown in more detail in FIGS. 2A-C and the second part of the joining system is shown in more detail in FIGS. 5A-B.

FIG. 2A is a perspective view of a first part 3 of the joining system. The first part 3 comprises an outer box element 10 and an internal box element 20. The outer box element 10, which is also illustrated in FIGS. 3A-B, where it is shown rotated 90 degrees relative to the variant shown in FIGS. 2A-C, and FIG. 3B illustrate a side view of the outer box element viewed in the direction into the box element 10, and rotated 90 degrees relative to FIGS. 2A-C.

The outer box element 10 is composed of a box profile with four lateral surfaces 14 as indicated in FIG. 3A, and a rear plate 15, as indicated in FIG. 2B and FIG. 3B. These form the partly closed box element 10 which has an open side for insertion of the internal box element 20. The outer box element 10 is terminated by a termination edge 17, which will be aligned with a surface of the element wherein it is cast, thereby preventing the formation of any projecting parts. The outer box element 10 further comprises attachment device 11 for the attachment of reinforcing elements 5, employed when it is cast in an element. The attachment devices 11 are arranged at two opposite lateral surfaces 14 of the outer box element 10 and have through-going holes 16, which in an embodiment may have at least one internally threaded portion (not shown). These attachment devices are usually welded to the lateral surfaces 14 of the box element 10. In a second variant the attachment devices may also be composed of suitable portions of the lateral surfaces of the box element for attaching reinforcement, for example by welding. The box element 10, moreover, has cut-outs 12 in the side of a lateral surface facing into the box element towards an opposite lateral surface. In the embodiment illustrated in the figure there are two cut-outs 12 on two oppositely directed lateral surfaces 14, which in turn are opposite the lateral surfaces 14 to which the attachment devices 11 are fixed. A person skilled in the art will appreciate that the solution explained herein is not an absolutely essential configuration. The cut-outs 12 in the illustrated example pass through the lateral surfaces 14 and an external cap 13 is provided that covers the through-going cut-outs on the outside of the box element 10 in order to prevent casting material from flowing into the box element during casting.

As illustrated in FIGS. 2A and 2B the internal box element 20 has a length that causes it to project from the outer box element 10 in an assembled position. To this projecting portion a joining element in the form of a plate 22, whose area is greater than the cross section of both the internal box element 20 and the outer box element 10, is mounted on the internal box element 20, which can be seen from FIG. 2C. The internal box element 20 further comprises a locking device in the form of a snap-in locking device which works in conjunction with the cut-outs 12 in the outer box element 10. The locking device comprises two holes 23 which pass through two lateral surfaces 21 of the internal box element 20. Into these holes 23 is inserted a sleeve 24 that extends from one hole 23 into the second 23. In the sleeve 24 are mounted two locking elements 25 with an intermediate spring element 26 that presses the locking pieces away from each other in the direction out of the sleeve 24, and thereby also into the cut-out 12 in the outer box element 10 and into abutment against the caps 13, best illustrated in FIG. 2C. By this means locking of the internal box element 20 to the outer box element 10 is achieved. The internal box element 20 is advantageously open at the end that is to be inserted into the outer box element 10, as can be seen from FIG. 4A which illustrates the internal box element 20 viewed from the side that is first inserted into the outer box element 10. In this figure the sleeve 24 and the projecting locking elements 25 can also be seen. Other snap-in locking devices may of course also be envisaged.

The joining element in the form of the plate 22 may also be provided with through-going holes 27 to the interior of the internal box element 20. Two small holes 27 are illustrated in the figures. These holes or a slightly larger hole may be provided in the plate 22 either in order to inspect whether the locking device is in a locked position, to install devices to enable the locking elements to be pulled into a recessed position and/or to add casting material to the interior of the internal box element while casting together the elements that are to be joined.

The reinforcing elements with which the outer box element 10 is secured to the cast of the element may be provided with a threaded portion 6 on an end that works in conjunction with the internal threaded portion of the attachment devices 11 and at the other end a stopper element 7 may be attached, as illustrated in FIGS. 2A, 2B, so that it is securely attached to the cast. Completely different types of reinforcing elements may of course also be envisaged, since this is not a material part of the invention, as a person skilled in the art will understand.

FIGS. 5A and 5B illustrate two views of an embodiment of the second part of the joining device as illustrated in FIG. 1, mounted on a beam. This second part of the joining device comprises a plate element 30 which is mounted on an end of a beam 2. The plate element 30 comprises a cut-out 31 which may possibly be provided with small guide surfaces 32. A lead-in 35 is further provided in the rear edge of the plate element 30.

When joining the two parts of the joining device, in this case mounted on a pillar and a beam, the beam with the plate element 30 will be lifted and lowered towards the joining element 22 (FIG. 2A) in the upper edge thereof. The beam with the plate element are lowered so that the edge of the cut-out 31 remains abutting against and around the part of the internal box element 20 that projects from the outer box element. In one portion therefore the cut-out 31 is complementary to an external cross section of the internal box element. The weight of the beam will press the edge of the cut-out 31 in the plate element 30 against the internal box element 20, thereby transferring forces. When the beam is lowered into abutment, the joining element 22 of the internal box element will be inserted in the cut-out 35 in the lower edge and rear edge of the plate element 30. In this way the plate element 30 is mounted between the joining element 22 and the surface of the pillar. The joining element 22 is mounted between the beam and the plate element 30. The shape of the cut-out 31 is also complementary to that of the internal box element 20, thereby achieving an alignment of the elements relative to each other. The arrangement of the plate element 30 and the joining element 22 as described above thereby also restricts the movement of the two elements relative to each other in the longitudinal direction of the beam, and the shape of the cut-out 31 and the cross section of the internal box element 20 restrict movement of the two elements relative to each other across the longitudinal direction of the beam.

FIG. 6 illustrates two possible methods of attachment of a first part of a joining device according to the invention. In the first example, a first part 3 is mounted in the pillar 1 with reinforcing elements 5 with stopper elements 7 mounted on the end of the reinforcing element 5 which projects “freely” into the pillar 1. In the second example, two first parts 3 are mounted at two opposite sides of the pillar 1 and reinforcing elements extend from the attachment device 11 on one first part 3 to the attachment device 11′ on the second first part 3′, thereby achieving a very secure attachment of the parts 3, 3′.

The invention has now been explained by means of an embodiment, but a number of variants and modifications of this embodiment may, however, be envisaged which lie within the scope of the invention as defined in the following claims. The attachment device may be clean surfaces on the box element for welding points for reinforcing rods, there may also be several mounted on the same lateral surface or on several lateral surfaces. The cap covering the through-going projections may, for example, be a circumferential band or sleeve or other device that prevents casting material from infiltrating the outer box element. Different cross section variants may be envisaged for the internal box element and the cut-out in the plate element, which still provide good contact, force transfer and centering of the second part of the joining device relative to the first part. It may also be possible to secure outer box elements facing three or all four edges of a square pillar or also a pillar of another shape, e.g. round. In this case the open side of the outer box element may be of a shape that is complementary to the outside of the pillar. 

1-11. (canceled)
 12. A joining system for joining two elements, for example a pillar and a beam in a building construction, where a first part of the joining system adapted for attachment in one of the two elements during casting of the element, comprises an outer box element and at least one internal box element for insertion in the outer box element comprising a locking device for locking the internal box element to the outer box element and a joining element for cooperation with a second part of the joining system and where the second part of the joining system can be attached in the second of the two elements that have to be joined, characterized in that the locking device comprises a snap-in device, cooperating with cut-outs provided in the outer box element.
 13. A first part of a joining system comprising an outer box element adapted for attachment in one element during casting of the element, comprising attachment devices for attaching reinforcing elements, and an internal box element for insertion in the outer box element comprising a locking device for locking the internal box element to the outer box element and a joining element for cooperation with a second part of the joining system, characterized in that the locking device comprises a snap-in device, cooperating with cut-outs provided in the outer box element.
 14. A first part of a joining system according to claim 2, characterized in that the snap-in device in the internal box element comprises two through-going holes provided in two oppositely directed lateral surfaces and a tubular piece provided in the two through-going holes, wherein two locking pieces are mounted in the tubular piece with an intermediate spring element, where the locking pieces work in conjunction with cut-outs in the outer box element.
 15. A first part of a joining system according to claim 2, characterized in that the cut-outs in the outer box element are in the form of two through-going holes in two oppositely directed sides of the outer box element with an externally mounted cap.
 16. A first part of a joining system according to claim 2, characterized in that the cut-outs in the outer box element are internal grooves.
 17. A first part of a joining system according to claim 3, characterized in that the cut-outs in the outer box element and the locking pieces in the snap-in device have corresponding cross sectional shapes.
 18. A first part of a joining system according to claims 2, characterized in that the outer box element comprises four surrounding sides and a rear side, thereby forming a partly closed box with an open side facing out of the element wherein the internal box element has to be mounted.
 19. A first part of a joining system according to claims 2, characterized in that the internal box element mounted in the outer box element has a length that causes a portion to project a length out of the outer box element, and the internal box element has a joining element in the form of a plate element mounted on the projecting portion of the internal box element.
 20. A joining system according to claim 1, characterized in that the second part of the joining system comprises a plate element mounted on the part of the second element facing the first part, where the plate element comprises a cut-out complementary to the projecting portion of the internal box element of the first part of the joining system.
 21. The use of a joining system according to claim 1, where the first part of the joining system is cast into a pillar.
 22. The use of a joining system according to claim 1, where both parts of the joining system are mounted in cast elements. 